Twitter On Fire! Traffic More Than Doubles In March

Twitter's growth chart continues to look incredible. The messaging/microblogging service attracted 9.3 million U.S. unique visitors to its site in March, up 131% over February, according to comScore. That's more than 5 million new visitors than the site had in February.

In an interesting blog post, comScore also notes that Twitter users seem to be news junkies. They are 2 to 3 times as likely as average Web users to visit top news sites -- especially Time Warner's (TWX) CNN.com.

Here's that traffic chart:

This isn't the perfect way to measure Twitter's user growth, as it includes people who visit Twitter.com but aren't Twitter users. But it also doesn't include mobile-only users, desktop-app users, foreigners, etc. Either way, it seems directionally correct -- and is very impressive.